reference objects without materials
OKAY ! So finally, after playing around with various scripts found on this website, assembling them, we found out  we had taken it the wrong way, as blender workflow is different from maya. The material is applied after in maya, and before in blender. 
The solution is a simple script that asks objects from the scene to be applied a premade material. In maya, naming is important for referencing, so our objects always have the same name. It's a bit fastidious to enter each name individually the first time, but it works out for us, as we simply run the script for each panel thereafter.

Here's our frankenbaby: (replace lama with whatever name you have)

import bpy
ob = bpy.data.objects.get("lama")

# Get material
mat = bpy.data.materials.get("Lamamat")
if mat is None:
    # create material
    mat = bpy.data.materials.new(name="Lamamat")

# Assign it to object
if ob.data.materials:
    # assign to 1st material slot
    ob.data.materials[0] = mat
else:
    # no slots
    ob.data.materials.append(mat)